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Date:   Tue, 21 Sep 2021 14:53:34 -0700
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Subject: Re: [PATCH v2 2/2] mm/debug: sync up latest migrate_reason to
 migrate_reason_names
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From:   John Hubbard <jhubbard@nvidia.com>
To:     "Huang, Ying" <ying.huang@intel.com>,
        Weizhao Ouyang <o451686892@gmail.com>
Cc:     Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Anshuman Khandual <khandual@linux.vnet.ibm.com>,
        Michal Hocko <mhocko@suse.com>,
        Pavel Tatashin <pasha.tatashin@soleen.com>,
        Yang Shi <yang.shi@linux.alibaba.com>, Zi Yan <ziy@nvidia.com>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Minchan Kim <minchan@kernel.org>,
        Mina Almasry <almasrymina@google.com>,
        "Matthew Wilcox (Oracle)" <willy@infradead.org>,
        Oscar Salvador <osalvador@suse.de>, Wei Xu <weixugc@google.com>
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On 9/21/21 11:00, John Hubbard wrote:
> On 9/21/21 07:06, Huang, Ying wrote:
> ...
>>>> Can we add BUILD_BUG_ON() somewhere to capture at least some
>>>> synchronization issue?
>>>
>>> Hi Huang, we discussed this in the v1 thread with you and John, seems you
>>> missed it. Now we just add a comment to do the synchronization, and we can
>>> figure out a more general way to use strings which in trace_events straight.
>>
>> Got it!  And I think we can add the BUILD_BUG_ON() now and delete it
>> when we have a better solution to deal with that.  But if you can work
>> out a better solution quickly, that's fine to ignore this.
>>
> 
> I have a solution now, it's basically what I sent earlier. There appears to be
> some confusion about it. I'll send it out as a patch that builds on top of
> these two, hopefully in a few hours, if no problems pop up during testing.
> 

Oh OK, I think the confusion was on my end: you are hoping to integrate the
TRACE_DEFINE_ENUM in with this. Let me take a peek there, because otherwise,
we can only reduce, but not fully remove the duplication.

thanks,
-- 
John Hubbard
NVIDIA